WCF 4 Behavior

http://blogs.msdn.com/b/kaevans/archive/2006/10/01/simple-wcf-service-behavior-inspect-messages-through-debug-output.aspx(WCF Service Behavior: Inspect Messages)

http://blogs.msdn.com/b/stcheng/archive/2009/02/18/wcf-secure-a-dynamically-added-message-header-via-behavior-extension-part-1.aspx(WCF Contract Behavior)

http://www.codeproject.com/Articles/37156/Focus-on-the-Extension-of-WCF-Behavior(Focus on the Extension of WCF Behavior)